A process for copper film deposition by pyrolysis of organic copper materials

A new technique of copper (Cu) film deposition by simple pyrolysis of copper hexafluoroacetylacetonate vinyltrimethylsilane [Cu¹⁺(hfac)(vtms)] in liquid phase has been proposed. The Cu films were deposited in air and nitrogen (N2) ambiences as a function of substrate temperature. Both Cu films show grain-like structures, and the grain size increased with increasing deposition temperature. X-ray diffraction patterns for all Cu films deposited in air and N₂ show the diffraction peaks corresponding to (111), (200), (220), and (311) crystal planes of Cu. The difference in lattice constant between the deposited Cu films and bulk Cu is less than 0.3%. The Cu films contain oxygen (O), carbon (C), and fluorine (F) as impurities. The relative concentrations of O, C, and F atoms are less than 10 atom %. The relative Cu concentrations in the films are over 80 atom %. The resistivity values for Cu films deposited at 250°C in air and N₂ ambiences were 65 and 46 μΩ-cm, respectively. The differences between this deposition method and metallorganic chemical vapor deposition is also discussed.